| /* |
| * Copyright (C) 2013 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package android.support.v4.util; |
| |
| class ContainerHelpers { |
| static final int[] EMPTY_INTS = new int[0]; |
| static final long[] EMPTY_LONGS = new long[0]; |
| static final Object[] EMPTY_OBJECTS = new Object[0]; |
| |
| public static int idealIntArraySize(int need) { |
| return idealByteArraySize(need * 4) / 4; |
| } |
| |
| public static int idealLongArraySize(int need) { |
| return idealByteArraySize(need * 8) / 8; |
| } |
| |
| public static int idealByteArraySize(int need) { |
| for (int i = 4; i < 32; i++) |
| if (need <= (1 << i) - 12) |
| return (1 << i) - 12; |
| |
| return need; |
| } |
| |
| public static boolean equal(Object a, Object b) { |
| return a == b || (a != null && a.equals(b)); |
| } |
| |
| // This is Arrays.binarySearch(), but doesn't do any argument validation. |
| static int binarySearch(int[] array, int size, int value) { |
| int lo = 0; |
| int hi = size - 1; |
| |
| while (lo <= hi) { |
| int mid = (lo + hi) >>> 1; |
| int midVal = array[mid]; |
| |
| if (midVal < value) { |
| lo = mid + 1; |
| } else if (midVal > value) { |
| hi = mid - 1; |
| } else { |
| return mid; // value found |
| } |
| } |
| return ~lo; // value not present |
| } |
| |
| static int binarySearch(long[] array, int size, long value) { |
| int lo = 0; |
| int hi = size - 1; |
| |
| while (lo <= hi) { |
| final int mid = (lo + hi) >>> 1; |
| final long midVal = array[mid]; |
| |
| if (midVal < value) { |
| lo = mid + 1; |
| } else if (midVal > value) { |
| hi = mid - 1; |
| } else { |
| return mid; // value found |
| } |
| } |
| return ~lo; // value not present |
| } |
| } |